18F-Fluoroethylcholine (18F-FEC) PET/CT is well established for the detection of prostate cancer recurrence. However, its specificity is sometimes impaired by false-positive findings. In the present case, atypical cancer recurrence in the right distal lower leg was suspected on 18F-FEC PET/CT in a patient with a history of prostate cancer and an increased prostate-specific antigen level. Using a real-time PET/ultrasound fusion technique, the tumor was localized and a biopsy carried out, leading to a final diagnosis of peripheral schwannoma.